Cyclic Climate Change and How We Know Excess Carbon is Going to FSU

These are extracted from responses I posted on reddit.

Context Question in Thread: "To me, as someone who has no real opinions on the matter (I don't know the facts so I refuse to form an opinion), all this article tells me is that 2013, 2006, and 2003 were above average in mean temperature for the past 100 years. What it doesn't say is that the global mean temperature has been steadily increasing over the past century or so, and doesn't give a reason why we know there wasn't a trend of global cooling from, say, 1700-1900, before we were records were kept or kept reliably. I'm not saying those things aren't said elsewhere, just that this article is useless and does nothing to prove global warming is real. No one disputes that the climate changes, just some think it's supposed to, and that it goes in cycles."

Cycles related to climate change, and why we should be worried 

here is a long term graph of carbon emissions over the past 800,000 years. You'll see carbon dioxide and temperature are variables that stay very close to each other. Because the time scales are so small, you cannot see that temperature lags behind carbon slightly (slightly in large timescales that is).

You'll see where we are at now is off the chart. Literally. We have been experiencing, and can expect to experience further, temperatures that no homo sapiens has ever experienced. Now that isn't so much about the temperature, but whether or not the plants and animals we need to survive will be around anymore. True story. The earth has been hotter and has had higher carbon concentrations in the past during the Eocene. Problem is that occurred over millions of years, and ours is occurring on timescales of decades.

Our main concern with climate change is not that we cannot adapt, our main concern is that we cannot adapt fast enough (and by we I mean all of the living matter on this planet that we depend on). Now that should scare you cycles or not, however we have damn good evidence the warming we are seeing is not part of a cycle. There are three majors cycles that the Earth goes through as far as temperature is concerned. One is the procession of the earth on it's axis. The earth wobbles on it's axis like a spinning top does. The north star isn't always north, in fact the Earth wobbles between 22 and 25 degrees (my numbers may be slightly off as I'm just recalling in my head but the numbers are damn close) we are at 22.5 degrees. That snowball earth theory is likely because of this effect.

Now you might be scratching you head with good reason, because the earth's tilt seems like it shouldn't have anything to do with temperature. Turns out it gets into this whole unequal heating and cooling thing that feeds back into glaciers and temperatures that is a little complicated to explain, so for now you are just going to have to trust me.

There is also the ellipse of the earth (how close earth is to the sun) then there is the solar cycle which is the intensity of the sun, is related to magnetic do dads of the sun and happens every 11 years. Then there is the long term geologic carbon cycle which takes too damn long. The carbon cycle essentially has two knobs.

1. Subduction, or tectonic plates sliding around each other like sex panthers and causing lots of lava explosions. This gets things hot and spicy.
2. The other is less sexy and is called silicate weathering. This is rocks turning air carbon into stored carbon essentially.

Good news is all that sexy lava explosions causes an atmosphere that silicate rocks like for converting their shiz. So over long time scales silicate weathering will probably save the day on carbon emissions. Problem is, it's on time scales of about, oh, human existence. And that is if we stopped emitting carbon, which, ha, we clearly are not. So that's poopy.

Now about all that volcano hub bub you keep hearing about. Volcanoes are weird but essentially they emit a lot of sulfur particles into the stratosphere which cools stuff down quite a bit. The thing is, scientists know about these, and all of the other cycles I described plus a lot more.

Here's a graph of predicted temperatures using only natural processes, and then a graph including anthropogenic (human) forcings (essentially our carbon emissions).

The main line is observed trends. Whelp, my hands are gettin tired, so I'm just going to stop here, but I am more than happy to answer whatever questions you might have (to the best of my ability). Cheers!

Context Question in Thread

 Fully prepared to be downvoted into oblivion, but here goes:

I see two graphs:

• One over hundreds of thousands of years in which the CO2 is horribly off the scale, and
• Another saying observed temperatures are higher than predictions made for the last 100 years.

With respect to the first graph, two lines that follow each other do not indicate causation. Even if one slightly trails the other. If the two measures are inextricably linked, given the observed CO2 is twice as high it normally gets, wouldn't the Antarctic temps be around 8 or more degrees by now? Or is the lag long enough we can't see it on the graph?

The second graph clearly indicates temperatures more than scientist predictions. But given we're seeing about 100 years here, are these increases actually statistically significant in the context of the 800,000 year graph above it? Over what period of time are these "predictions" made?

There's a disconnect here for me that I'm keen to be educated on.

EDIT: Ok, this page definitely helps by explaining a few things - in particular the relationship between CO2 and temperature:http://www.skepticalscience.com/climate-change-little-ice-age-medieval-warm-period-intermediate.htm

How we know extra carbon is going to FSU

These are excellent questions! You are absolutely correct, correlation does not equal causation, and that is a common flaw in scientific literature.

The good thing is that we understand quite well the theory behind how carbon dioxide impacts temperatures. As we all remember, carbon dioxide is a greenhouse gas, but what does that mean besides the shitty, my car gets hot in the summer metaphor? To start I need to give you a little nerdy background on what is called, the stefan Boltzmann law. Essentially, earth is called a black body, which means it can play all the chords on the energy guitar (electromagnetic energy is a continuum that starts with radio waves, then microwaves, then infared (essentially heat) then visual light, then ultraviolet, then x rays, gamma rays etc. Think of these like guitar strings that go up in frequency) here's a chart.

(We only see visual light because it is within the frequency our eyes understand.) Since the earth can play all the chords, it's emission of energy back out to space (it's music back out so to speak) follows a curve according to it's mass. The peak of that curve is what you can "see" coming off that body. The sun looks yellow because it is big enough to EMIT in the visible light spectrum at yellow. Earth isn't big enough or hot enough to do that so it emits below visible light that we cannot see. what is important is that ideally a black body (all stringed guitar) like the earth should play a tune that looks like this if there is no interference.

There are other energy guitars though that don't have all their strings. Some energy guitars only have one cord, like the B string (but instead of b it is ultraviolet radiation, or more specifically a certain frequency of wave.) Carbon Dioxide, like water vapor, nitrous oxide, and methane, is a molecule that can have a dipole moment, meaning it can be an energy guitar. But what is that? It mean's it can get all goofy looking and become asymmetrical like this but again what the heck does that mean.

Essentially they can radiate energy back out when they are all goofed up (they can play a note on their energy guitar.) It is important to note that these molecules need energy in (like the strum of a finger, to play their note. They are like big mimickers. They hear a b note and they play a b note back. (this has to do with electrons and excitement but it is a bit too complicated for this). The thing is, earth is emitting it's energy AWAY from itself, and these energy strings emit energy in ALL directions, meaning a bunch of it travels back down to earth. But why don't we worry about gases like oxygen?

Oxygen can never ever, ever, have a dipole moment, because it's too neat and orderly it can never be assymetrical no matter how you stretch it. That is why we worry about a select few gases.

Now that you've learned about all of these energy guitars. here is a graph of the earth's emissions spectrum. You will notice it is not that nice curve we saw at that beginning, and that is because molecules like carbon dioxide are using some of that energy and radiating it back out (but not away) from the earth. They are essentially eating at the earth's emissions spectrum. THe earth's emisssion spectrum is essentially a big air conditioner, it's a huge heat dissipator. And so when we eat a chunk out of the air conditioner, it gets a bit hotter because that energy stays here on earth. Carbon dioxde as we can see is particularly bad because it LOVES to eat at the chunk of the spectrum we have the most of, so it does a lot of damage (it nerdy terms, it reemits at the frequency that earth tries to get rid of the most) We don't like carbon dioxide because we are frequency prejudice. we don't like the frequency it reemits at (with good reason, it warms us the fuck up).

Actually we love carbon dioxide, because without it we would all be dead and cold. But too much of us makes shit get fucked up. Also, just a tidbit, scientists have known about carbon dioxde as a greenhouse gas for a long long time. In fact Servantes Arrenius (too lazy to spellcheck) first made an estimate of how hot it would get if we doubled C02 back before 1900. He was within a few degrees of our current models. That is because it is a pretty simple science. We know within a few degrees what's up, but what we are trying to figure out is things like weather patterns etc, or what exactly that warming means (precipitation, hurricanes etc). THAT is our big kick, we know relatively how hot it will get if x carbon is inputted into the system, and we've known for a long time.